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1
Lowe, Daniel Mark. "Extraction of chemical structures and reactions from the literature." Thesis, University of Cambridge, 2012. https://www.repository.cam.ac.uk/handle/1810/244727.
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The ever increasing quantity of chemical literature necessitates the creation of automated techniques for extracting relevant information. This work focuses on two aspects: the conversion of chemical names to computer readable structure representations and the extraction of chemical reactions from text. Chemical names are a common way of communicating chemical structure information. OPSIN (Open Parser for Systematic IUPAC Nomenclature), an open source, freely available algorithm for converting chemical names to structures was developed. OPSIN employs a regular grammar to direct tokenisation and parsing leading to the generation of an XML parse tree. Nomenclature operations are applied successively to the tree with many requiring the manipulation of an in-memory connection table representation of the structure under construction. Areas of nomenclature supported are described with attention being drawn to difficulties that may be encountered in name to structure conversion. Results on sets of generated names and names extracted from patents are presented. On generated names, recall of between 96.2% and 99.0% was achieved with a lower bound of 97.9% on precision with all results either being comparable or superior to the tested commercial solutions. On the patent names OPSIN s recall was 2-10% higher than the tested solutions when the patent names were processed as found in the patents. The uses of OPSIN as a web service and as a tool for identifying chemical names in text are shown to demonstrate the direct utility of this algorithm. A software system for extracting chemical reactions from the text of chemical patents was developed. The system relies on the output of ChemicalTagger, a tool for tagging words and identifying phrases of importance in experimental chemistry text. Improvements to this tool required to facilitate this task are documented. The structure of chemical entities are where possible determined using OPSIN in conjunction with a dictionary of name to structure relationships. Extracted reactions are atom mapped to confirm that they are chemically consistent. 424,621 atom mapped reactions were extracted from 65,034 organic chemistry USPTO patents. On a sample of 100 of these extracted reactions chemical entities were identified with 96.4% recall and 88.9% precision. Quantities could be associated with reagents in 98.8% of cases and 64.9% of cases for products whilst the correct role was assigned to chemical entities in 91.8% of cases. Qualitatively the system captured the essence of the reaction in 95% of cases. This system is expected to be useful in the creation of searchable databases of reactions from chemical patents and in facilitating analysis of the properties of large populations of reactions.
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Intaranont, Noramon. "Selective lithium extraction from salt solutions by chemical reaction with FePO4." Thesis, University of Southampton, 2015. https://eprints.soton.ac.uk/382486/.
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The spectacular increase in lithium battery applications has raised the question of whether global lithium resources will be enough in the future. Experts in the field have estimated that the existing lithium resources will probably be sufficient to support demands until the year 2100, assuming that lithium batteries are recycled. Without lithium batteries being recycled, the resources are expected to be depleted in 50 years’ time. Therefore, there is a great interest in developing better methods of lithium recycling from batteries, and also, better methods of lithium extraction from natural resources. Currently, lithium is extracted from natural brines via the lime soda evaporation process, i.e. a solar evaporation plus chemical plant process, which takes between 12 and 24 months. The drawbacks of this process are that it is complex, slow and inefficient. Also, the currently available methods of lithium recycling from batteries are too complex and expensive. Thus, the main objective of this work is to develop a novel, inexpensive and less timeconsuming approach to recover lithium chemically, from the lithium salts (lithium sources) that contain other metal cations. The new process is also based on environmental concerns. A battery material, lithium iron phosphate (LiFePO4) has the olivine structure and heterosite structure once it discharges to iron phosphate (FePO4). This structure shows excellent properties of the charge/discharge reversibility. A few studies on the heterosite FePO4 have reported that it is more selective for lithium ions (Li+) over other cations. The main advantages of this structure are the small potential differences of the redox couple, i.e. Fe(II)/Fe(III), and the stability of LiFePO4 over a wide range of acid-based conditions in an aqueous solution. This work investigates a novel process that may be superior to the lime soda evaporation process for extracting lithium. Heterosite FePO4 was employed to selectively remove Li+ from lithium sources with the support of a reducing agent, i.e. sodium thiosulphate (Na2S2O3). The resulting LiFePO4 can be directly sent not only to lithium battery industries, but also to other industrial uses. In principle, the other cations could be retrieved back into their sources. The novel process was examined and demonstrated lithium insertion into a heterosite FePO4, working as a framework, in aqueous salt solutions. The evaluation of this process is presented by the Li+ uptake value. The amount of Li+ uptake can be up to 46 mgLi +/gsolid where other cations (i.e. sodium, potassium, and magnesium) can take less than 3 mg/gsolid, using this process. Furthermore. This work could also be developed for future lithium recycling processes.
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Van, Winkle Carolyn. "Forensic DNA Extraction Strategies for PCR Analysis." Thesis, University of North Texas, 1998. https://digital.library.unt.edu/ark:/67531/metadc278269/.
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There is a transition nationwide on the analysis of forensic evidentiary stains containing biological material from traditional serology to Polymerase Chain Reaction (PCR) methodologies. The increased sensitivity of PCR, the limited number of alleles at each locus, and the necessity of producing unambiguous data for entry into the FBI's Combined DNA Index System make this study of extraction procedures of utmost importance. A "single tube" extraction procedure for blood stains collected onto FTA™ paper and a modified differential nonorganic extraction method from spermatozoa containing
mixed stains were analyzed and compared. The extraction success was evaluated by amplification and typing of the amplified fragment length polymorphism, D1S80. These modifications of the nonorganic method utilized gave an improved separation of the spermatozoa-containing mixed stains.
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Dahlberg, Gunnar. "Implementation and evaluation of a text extraction tool for adverse drug reaction information." Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-134063.
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Inom ramen för Världshälsoorganisationens (WHO:s) internationella biverkningsprogram rapporterar sjukvårdspersonal och patienter misstänkta läkemedelsbiverkningar i form av spontana biverkningsrapporter som via nationella myndigheter skickas till Uppsala Monitoring Centre (UMC). Hos UMC lagras rapporterna i VigiBase, WHO:s biverkningsdatabas. Rapporterna i VigiBase analyseras med hjälp av statistiska metoder för att hitta potentiella samband mellan läkemedel och biverkningar. Funna samband utvärderas i flera steg där ett tidigt steg i utvärderingen är att studera den medicinska litteraturen för att se om sambandet redan är känt sedan tidigare (tidigare kända samband filtreras bort från fortsatt analys). Att manuellt leta efter samband mellan ett visst läkemedel och en viss biverkan är tidskrävande. I den här studien har vi utvecklat ett verktyg för att automatiskt leta efter medicinska biverkningstermer i medicinsk litteratur och spara funna samband i ett strukturerat format. I verktyget har vi implementerat och integrerat funktionalitet för att söka efter medicinska biverkningar på olika sätt (utnyttja synonymer,ta bort ändelser på ord, ta bort ord som saknar betydelse, godtycklig ordföljd och stavfel). Verktygets prestanda har utvärderats på manuellt extraherade medicinska termer från SPC-texter (texter från läkemedels bipacksedlar) och på biverkningstexter från Martindale (medicinsk referenslitteratur för information om läkemedel och substanser) där WHO-ART- och MedDRA-terminologierna har använts som källa för biverkningstermer. Studien visar att sofistikerad textextraktion avsevärt kan förbättra identifieringen av biverkningstermer i biverkningstexter jämfört med en ordagrann extraktion.Background: Initial review of potential safety issues related to the use of medicines involves reading and searching existing medical literature sources for known associations of drug and adverse drug reactions (ADRs), so that they can be excluded from further analysis. The task is labor demanding and time consuming. Objective: To develop a text extraction tool to automatically identify ADR information from medical adverse effects texts. Evaluate the performance of the tool’s underlying text extraction algorithm and identify what parts of the algorithm contributed to the performance. Method: A text extraction tool was implemented on the .NET platform with functionality for preprocessing text (removal of stop words, Porter stemming and use of synonyms) and matching medical terms using permutations of words and spelling variations (Soundex, Levenshtein distance and Longest common subsequence distance). Its performance was evaluated on both manually extracted medical terms (semi-structuredtexts) from summary of product characteristics (SPC) texts and unstructured adverse effects texts from Martindale (i.e. a medical reference for information about drugs andmedicines) using the WHO-ART and MedDRA medical term dictionaries. Results: For the SPC data set, a verbatim match identified 72% of the SPC terms. The text extraction tool correctly matched 87% of the SPC terms while producing one false positive match using removal of stop words, Porter stemming, synonyms and permutations. The use of the full MedDRA hierarchy contributed the most to performance. Sophisticated text algorithms together contributed roughly equally to the performance. Phonetic codes (i.e. Soundex) is evidently inferior to string distance measures (i.e. Levenshtein distance and Longest common subsequence distance) for fuzzy matching in our implementation. The string distance measures increased the number of matched SPC terms, but at the expense of generating false positive matches. Results from Martindaleshow that 90% of the identified medical terms were correct. The majority of false positive matches were caused by extracting medical terms not describing ADRs. Conclusion: Sophisticated text extraction can considerably improve the identification of ADR information from adverse effects texts compared to a verbatim extraction.
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Rezaei, Karamatollah. "Developing an on-line extraction-reaction process for lipids using supercritical carbon dioxide." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/NQ46909.pdf.
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Mandeville, Sylvain. "Extraction and identification of Maillard reaction precursors from shrimp and GCMS investigation of related Maillard model systems." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=41704.
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Proximate analysis of the commercial shrimp meat waste samples indicated the presence of 94.6% protein and 4.2% fat on a dry basis. The HPLC analysis revealed the presence of 17 amino acids (proline most abundant) and 7 sugars (ribose being the most abundant). The changes in the concentration of the amino acids and sugars after heat treatment, are explained based on their interaction through the Maillard reaction and by the thermal hydrolysis of proteins and polysaccharides present in tissue. Carotenoid pigments ($ beta$-carotene, canthaxanthin, astacene, and astaxanthin monopalmitate) were extracted and separated by thick layer chromatography. Their structures were identified tentatively by thick layer chromatography (TLC) and subsequently confirmed by Fourier transformed infrared (FT-IR) spectroscopy. Lipids were separated and categorized into glycerides, sterols, and phospholipids by thin layer chromatography while flavor-active components were extracted by different organic solvents into acidic, basic, and neutral fractions and their sensory properties determined. The flavor profile of the raw and cooked shrimp meat waste revealed the presence of 59 compounds in raw shrimp compared to 44 in cooked. The components identified were of different functional groups, including fatty acid esters, long chain alcohols, aldehydes, ketanes and hydrocarbons. Many fractions provided desirable aroma (nutty, fruity, floral, green woody, meaty) indicating the presence of important flavor compounds in the commercial shrimp waste.Model studies were carried out under different experimental conditions (water content, pH), to observe the influence of these parameters on the formation of Maillard reaction products. Furthermore, a comparative study between direct injection of the aqueous solutions and its organic extracts was conducted. The direct injection of aqueous solutions revealed the presence of many water soluble components that were not detected by organic solvent extraction such as droserone and 3,9-diazatricyclo$ lbrack7.3.0.0 sp{*}.3 sp{*}.7 sp{ *} rbrack$-dodecan-2,8-dione while maltoxazine and acetanilide are example of compounds identified only in the dichloromethane extracts. Results also demonstrated that monosaccharides affected the yield of the compounds produced whereas the amino acids influenced the sensory properties of these models. Fructose and ribose were found to be the most reactive sugars in their respective categories. Thiazoles were found to be more water soluble whereas $ beta$-carbolines were more abundant in the organic extracts. The influence of water content was investigated in model systems containing fructose or glucose. It was found that water free systems decreased the yield of pyrazines and thiazoles while the formation of pyrrole and pyridine derivatives increased under dry heating conditions. The formation of Maillard reaction products were studied under different pH conditions in order to assess the effect of pH on the formation of heterocyclic compounds. Pyrazine and furan derivatives were the most affected by pH and alanine was found to be a better nitrogen source than lysine in the formation of pyrazines under different pH conditions. Finally, based on energy minimization studies using MM2 force field, a plausible mechanism was proposed for the formation of maltol in Maillard model systems.
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Söldner, Anika [Verfasser], and Burkhard [Akademischer Betreuer] König. "Deep Eutectic Solvents as Extraction, Reaction and Detection Media for Inorganic Compounds / Anika Söldner ; Betreuer: Burkhard König." Regensburg : Universitätsbibliothek Regensburg, 2020. http://d-nb.info/1210728869/34.
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Zachén, Esbjörn. "Extraction of tool reaction forces using LS-DYNA and its use in Autoform sheet metal forming simulation." Thesis, Blekinge Tekniska Högskola, Institutionen för maskinteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-17886.
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In product development there is still potential to decrease lead times with faster and more accurate simulations. The objective of this thesis was to study whether Finite Element (FE) simulations using explicit LS-DYNA to extract reaction forces from sheet metal forming tools during forming, could be used to improve existing FE models in sheet metal forming software AutoForm.To begin with, the solid CAD-model of the stamping dies were meshed with tetrahedral elements in CATIA and imported into LS-DYNA. In combination with sheet mesh and milling surface meshes from AutoForm, an explicit model was realized. Contacts between sheet mesh and milling surface meshes used the so-called sheet forming contact. The resulting reaction forces were extracted and used in a simulation using the AutoForm software. Resulting simulation was compared to a scan of the physical sheet metal after forming.The direct transfer of reaction forces from LS-DYNA to AutoForm did however not result in the same pressure distribution in AutoForm. The AutoForm simulations using results from LS-DYNA were slightly worse than standard AutoForm simulations.Further work is needed to try and perhaps implement an implicit solution after an initial explicit solution.Inom produktutveckling finns möjligheter att förkorta ledtider genom snabbare och mera korrekta simuleringar. Syftet med detta arbetet var att undersöka huruvida resultat från explicit LS-DYNA kunde användas för att förbättra nuvarande plåtformningssimuleringar i AutoForm.Den solida CAD-modellen av verktyget meshades med tetraediska element i CATIA och importerades till LS-PrePost, tillsammans med fräsytsmeshar och plåtmesh från AutoForm. Kontakter etablerades mellan plåt och fräsytsmeshar med så kallad sheet forming contact. Modellen löstes sedan explicit. Resulterande reaktionskrafter på plåthållare exporterades till AutoForm och implementerades där. Resulterande simulering jämfördes mot en inskannad fysisk plåt efter plåtformning.Direkt implementering av reaktionskrafter på plåthållaren i AutoForm gav resultat som avvek mer mot inskannad plåt än nuvarande simuleringsstrategi. Direkt implementering av reaktionskrafter gav heller inte en tryckfördelning som liknade den som rapporterades av LS-DYNA.Mer arbete krävs för att om möjligt implementera en implicit lösning efter en initial explicit lösning.
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Lam, Yiu-pong, and 林耀邦. "Performance evaluation of the automated NucliSens easyMAG and Qiagen EZ1 Advanced XL nucleic acid extraction platform for detection of RNAand DNA viruses in clinical samples." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B46448020.
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Reising, Lauren Jane. "Effects of Active and Passive Spreading on Mixing and Reaction during Groundwater Remediation by Engineered Injection and Extraction." Thesis, University of Colorado at Boulder, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=10980544.
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During in situ groundwater remediation, a chemical or biological amendment is introduced into the aquifer to degrade the groundwater contaminant. In this type of remediation, mixing of the amendment and the contaminated groundwater, through molecular diffusion and pore-scale dispersion, is necessary for reaction to occur. Since the length scale of dispersion is small compared to the size of the contaminant plume, reactions are limited to a relatively narrow region where the amendment and contaminant are close enough to mix. Spreading, defined as the reconfiguration of the plume shape due to spatially-varying velocity fields, increases the size of the region where reaction occurs and increases concentration gradients, both of which can lead to enhanced mixing and reaction. Spreading can occur passively by heterogeneity of hydraulic conductivity or actively by engineered injection and extraction (EIE), in which clean water is injected or extracted at an array of wells surrounding the contaminant plume. Several studies have shown that active spreading by EIE enhances contaminant degradation in homogeneous porous media compared to remediation without EIE. Furthermore, studies have also shown that combining EIE with passive spreading by heterogeneity can lead to even more degradation compared to EIE alone. In this study, we investigate the relationship between passive and active spreading to better understand their combined impact on mixing and reaction during EIE. Using various combinations of heterogeneity patterns (e.g., high and low hydraulic conductivity inclusions) and simple injection and extraction flow fields typical to EIE, we determine how the particular spreading of the amendment and contaminant plume under each heterogeneity/flow field combination controls the amount of mixing and reaction enhancement. We find that the injection and extraction flow fields can be designed to complement the topological features generated from specific heterogeneity structures, thereby increasing the amount of mixing and reaction enhancement. Since the subsurface is inherently heterogeneous, insights gained from this research will provide crucial information for the optimal design of EIE systems in the field.
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Bowen, Isaac Brockbank. "Growth Characteristics of Lactobacillus wasatchensis and Its Detection and Enumeration Using Quantitative Polymerase Chain Reaction." DigitalCommons@USU, 2018. https://digitalcommons.usu.edu/etd/7273.
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There are numerous challenges encountered during the manufacturing and storage of cheese by both the large-scale and artesian producers. One such challenge has been the formation of late gassy defect, which occurs when gas is produced by certain lactic acid bacteria found in the cheese block during storage and aging over a three month time period. Negative consequences of late gas production are slits and cracks in the cheese block and puffy cheese packaging, which cause significant financial losses for manufacturers along with poor consumer acceptance.
Lactobacillus wasatchensis is one such lactic acid bacterium shown to produce gas during cheese storage. This bacterium has now been found in cheese samples exhibiting late gas defect in the Midwest and Western states. The goal of this study was to further characterize and understand the growth attributes of Lb. wasatchensis, and thereby gain some understanding on how it enters the cheese vats and if there are possible ways to limit or inhibit its subsequent growth. An additional goal was to determine if we could effectively extract Lb. wasatchensis DNA from cheese samples and visualize using the qPCR molecular technique. If possible, this detection method would allow a faster and more sensitive approach to determining if Lb. wasatchensis is present in cheese blocks, which would help manufacturers know how long they should age their cheeses.
It was discovered that Lb. wasatchensis does not survive processing through an industrial heat exchanger and therefore must be entering the cheese vats by other means such as: cross-contamination, biofilm formation or aerosolizing. We also showed growth of Lb. wasatchensis is limited at an increased salt-in-moisture ratio in cheese. Additionally, we found that Lb. wasatchensis DNA can be extracted from cheese and visualized using qPCR, although further experimentation is needed to optimize this method.
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Wrede, Fredrik. "An Explorative Parameter Sweep: Spatial-temporal Data Mining in Stochastic Reaction-diffusion Simulations." Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-280287.
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Stochastic reaction-diffusion simulations has become an efficient approach for modelling spatial aspects of intracellular biochemical reaction networks. By accounting for intrinsic noise due to low copy number of chemical species, stochastic reaction-diffusion simulations have the ability to more accurately predict and model biological systems. As with many simulations software, exploration of the parameters associated with the model can be needed to yield new knowledge about the underlying system. The exploration can be conducted by executing parameter sweeps for a model. However, with little or no prior knowledge about the modelled system, the effort for practitioners to explore the parameter space can get overwhelming. To account for this problem we perform a feasibility study on an explorative behavioural analysis of stochastic reaction-diffusion simulations by applying spatial-temporal data mining to large parameter sweeps. By reducing individual simulation outputs into a feature space involving simple time series and distribution analytics, we were able to find similar behaving simulations after performing an agglomerative hierarchical clustering.
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Ambushe, AA, RI McCrindle, and CME McCrindle. "Speciation of chromium in cow’s milk by solid-phase extraction/dynamic reaction cell inductively coupled plasma mass spectrometry (DRC-ICP-MS)." The Royal Society of Chemistry, 2009. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1001492.
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Chromium can act either as an essential micronutrient or a chemical carcinogen, depending on its
oxidation state. Of the two most stable chromium oxidation states, Cr(VI) is a known carcinogen, while
Cr(III) is an essential element. Determination of total Cr cannot therefore be used to evaluate food
safety of dairy products, as speciation is required for accurate assessment of potential toxicity. In this
study, total Cr was determined by DRC-ICP-MS after mineralisation of freeze-dried milk samples.
Chromabond NH2 ion-exchange columns were used to separate Cr(VI) from Cr(III). During the
separation process, Cr(VI) was selectively adsorbed onto the Chromabond NH2 column. The retained
Cr(VI) was subsequently eluted with two column volumes of 2 M HNO3 and diluted to a final volume
of 10 mL. After separation, the Cr(VI) was quantified by DRC-ICP-MS, using O2 as the reactive gas, to
alleviate polyatomic ion interference. An O2 gas flow rate of 0.85 ml/min and a high-pass rejection
parameter q (Rpq) ¼ 0.5, provided the best compromise signal-to-noise ratio. The method was
validated through determining the recovery in milk samples spiked with Cr(VI). The recoveries were
quantitative and ranged from 96.4 to 99.2%. A whole milk powder reference material (NIST SRM
8435) was used to evaluate the accuracy of the total Cr quantification method. The observed value
showed concordance with the certified value. The limits of detection (LOD) were 0.091 and 0.085 mg/L
for total Cr and Cr(VI), respectively. These findings are important for the determination of maximum
residue levels (MRLs) of Cr(VI) in dairy products.
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Gajdoš, Adam. "Parní turbína pro spalovnu odpadů." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2020. http://www.nusl.cz/ntk/nusl-417527.
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Diploma thesis deals with the design of the condensing steam turbine with power output 23.63 MW at 5000 rpm and an efficiency of 84.17% after optimization. The turbine contains one controlled steam extraction and four bleeds. The steam mass flow required by controlled steam extraction is 0-75 t/h of a total mass flow to the turbine 105 t/h. Design of the steam turbine is preceded by calculation of heat balance of the cycle. Then the thermodynamic and strength calculation of regulation stage and reaction staging flow channel are made. Thermodynamic calculation of the flow channel consists of preliminary and detailed calculation. It is detailed calculation that leads to the turbine parameters optimization. The design also includes gland sealing system and balance piston calculation. In addition to the strength calculation there is bearings load calculation included. In the end, the consumption diagram is made, showing the interval by which the turbine can be safely operated. Integrated part of the thesis is conceptual drawing of steam turbine section.
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Greeff, Mariska R. "The development, optimisation and evaluation of molecular methods to diagnose abalone tubercle mycosis (ATM) caused by Halioticida Noduliformans in South African abalone, Haliotis Midae." Thesis, University of the Western Cape, 2012. http://hdl.handle.net/11394/4033.
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Magister Scientiae (Biodiversity and Conservation Biology)Land-based abalone aquaculture in South Africa started in the early 1990s and is based on the local species Haliotis midae. This industry expanded with great success over the last decade. In 2006 abalone exhibiting typical clinical signs of tubercle mycosis was discovered for the first time in South African abalone culture facilities,posing a significant threat to the industry. Halioticida noduliformans, a fungus belonging to the Peronosporomycetes (formerly Oomycetes), has been identified as the causative agent of abalone tubercle mycosis (ATM). While diagnoses of this disease are currently done by gross observation and histopathology, these methods fail to be sensitive enough to identify the causative agent accurately and reliably.Molecular confirmation could provide for quicker more accurate diagnostic information. The aim of this study was to develop a DNA based molecular diagnostic test. Polymerase chain reaction (PCR) has been used to rapidly detect, characterise and identify a variety of organisms. Nucleotide sequences of the smalland large-subunit ribosomal ribonucleic acid (rRNA) and mitochondrial cytochrome oxidase subunit II (cox2) genes of H. noduliformans were compared with closely related Peronosporomycete gene sequences to identify potential PCR primer sites. H. noduliformans specific real-time quantitative PCR (Q-PCR) primer sets were designed and optimised for each of the selected genes. Results indicate that, although all tested primers sets could amplify fungal DNA, only the LSU and cox2 primer sets - v -demonstrated no cross-amplification with the closely related Peronosporomycete and non-fungal DNA tested in the present study. The H. noduliformans specific LSU primer set was chosen for further analysis and used for all subsequent real-time PCR assays. The lowest detection limit for the LSU primer set was evaluated by running Q-PCR on serial dilutions of known quantities of extracted H. noduliformans DNA.Serial dilutions were made in PCR grade water as well as in an abalone tissue matrix.The sensitivity of the Q-PCR reaction was determined to be 266 pg of H.noduliformans DNA per 25 μL reaction volume. However, inclusion of a nested PCR step, utilising universal fungal outer primers, followed by Q-PCR with the H.noduliformans LSU specific primers improved sensitivity to 0.266 pg of H.noduliformans DNA per 25 μL reaction volume. This equates to approximately 2.4spores per 25 μL reaction volume. DNA extraction protocols were optimised to ensure efficient and repeatable extraction of high quality fungal DNA from pure fungus and tissue samples spiked with known quantities of fungal DNA. PCR amplification efficiency and potential inhibition were examined for each extraction method. Results suggest that real-time PCR has great potential in monitoring and quantifying H. noduliformans on abalone culture facilities in South Africa.
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Tison, Erick. "Caractérisation de la zone de mélange d'un extracteur centrifuge à effet Couette utilisé en extraction liquide-liquide." Vandoeuvre-les-Nancy, INPL, 1996. http://www.theses.fr/1996INPL065N.
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Cette étude a pour objectif la caractérisation (hydrodynamique, propriétés d'émulseur et de réacteur chimique) de la zone de mélange d'un extracteur centrifuge mettant à profit l'écoulement de Couette-Taylor. Ce type d'appareil potentiellement utilisable pour certaines opérations du retraitement des combustibles nucléaires permet de réaliser des opérations d'extraction liquide-liquide avec réaction chimique
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Guardo, Zabaleta Alfredo. "Computational Fluid Dynamics Studies in Heat and Mass Transfer Phenomena in Packed Bed Extraction and Reaction Equipment: Special Attention to Supercritical Fluids Technology." Doctoral thesis, Universitat Politècnica de Catalunya, 2007. http://hdl.handle.net/10803/6455.
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El entendimiento de los fenómenos de transferencia de calor y de masa en medios porosos implica el estudio de modelos de transporte de fluidos en la fracción vacía del medio; este hecho es de fundamental importancia en muchos sistemas de Ingeniería Química, tal como en procesos de extracción o en reactores catalíticos. Los estudios de flujo realizados hasta ahora (teóricos y experimentales) usualmente tratan al medio poroso como un medio efectivo y homogéneo, y toman como válidas las propiedades medias del fluido. Este tipo de aproximación no tiene en cuenta la complejidad del flujo a través del espacio vacío del medio poroso, reduciendo la descripción del problema a promedios macroscópicos y propiedades efectivas. Sin embargo, estos detalles de los procesos locales de flujo pueden llegar a ser factores importantes que influencien el comportamiento de un proceso físico determinado que ocurre dentro del sistema, y son cruciales para entender el mecanismo detallado de, por ejemplo, fenómenos como la dispersión de calor, la dispersión de masa o el transporte entre interfaces.La Dinámica de Fluidos Computacional (CFD) como herramienta de modelado numérico permite obtener una visión mas aproximada y realista de los fenómenos de flujo de fluidos y los mecanismos de transferencia de calor y masa en lechos empacados, a través de la resolución de las ecuaciones de Navier - Stokes acopladas con los balances de materia y energía y con un modelo de turbulencia si es necesario. De esta forma, esta herramienta permite obtener los valores medios y/o fluctuantes de variables como la velocidad del fluido, la temperatura o la concentración de una especie en cualquier punto de la geometría del lecho empacado.
El objetivo de este proyecto es el de utilizar programas comerciales de simulación CFD para resolver el flujo de fluidos y la transferencia de calor y de masa en modelos bi/tri dimensionales de lechos empacados, desarrollando una estrategia de modelado aplicable al diseño de equipos para procesos de extracción o de reacción catalítica. Como referencia se tomaran procesos de tecnología supercrítica debido a la complejidad de los fenómenos de transporte involucrados en estas condiciones, así como a la disponibilidad de datos experimentales obtenidos previamente en nuestro grupo de investigación. Estos datos experimentales se utilizan como herramienta de validación de los modelos numéricos generados, y de las estrategias de simulación adoptadas y realizadas durante el desarrollo de este proyecto.
An understanding of the heat and mass transfer phenomena in a porous media implies the study of the fluid transport model within the void space; this fact is of fundamental importance to many chemical engineering systems such as packed bed extraction or catalytic reaction equipment. Experimental and theoretical studies of flow through such systems often treat the porous medium as an effectively homogeneous system and concentrate on the bulk properties of the flow. Such an approach neglects completely the complexities of the flow within the void space of the porous medium, reducing the description of the problem to macroscopic average or effective quantities. The details of this local flow process may, however, be the most important factor influencing the behavior of a given physical process occurring within the system, and are crucial to understanding the detailed mechanisms of, for example, heat and mass dispersion and interface transport.
Computational Fluid Dynamics as a simulation tool allows obtaining a more approached view of the fluid flow and heat and mass transfer mechanisms in fixed bed equipment, through the resolution of 3D Reynolds averaged transport equations, together with a turbulence model when needed. In this way, this tool permit to obtain mean and fluctuating flow and temperature values in any point of the bed.
The goal of this project is to use commercial available CFD codes for solving fluid flow and heat and mass transfer phenomena in two and three dimensional models of packed beds, developing a modeling strategy applicable to the design of packed bed chemical reaction and extraction equipment. Supercritical extraction and supercritical catalytic reaction processes will be taken as reference processes due to the complexity of the transport phenomena involved within this processes, and to the availability of experimental data in this field, obtained in the supercritical fluids research group of this university. The experimental data priory obtained by our research group will be used as validation data for the numerical models and strategies dopted and followed during the developing of the project.
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Price, Brendon. "Human Papillomavirus DNA extraction and genotype analysis by multiplex real time polymerase chain reaction from formalin fixed paraffin wax-embedded cervical carcinoma specimens." Master's thesis, Faculty of Health Sciences, 2019. http://hdl.handle.net/11427/31189.
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Introduction: Cervical squamous cell carcinoma is most commonly caused by persistent infection by high risk human papillomavirus (hrHPV) genotypes. The exact type of hrHPV varies geographically and is the basis for HPV–based vaccination for cervical squamous cell carcinoma prevention. Little is known regarding local hrHPV genotypes within the Western Cape population of South Africa. Aims and objectives: This was a pilot study aiming to extract of high quality genomic DNA from archival FFPE cervical squamous cell carcinoma cases and identify hrHPV genotypes by multiplex real time PCR (RT-PCR). Materials and methods: A retrospective search identified a total of 57 cases of cervical squamous cell carcinoma for the period 2004-2014. This was reduced to a final number of 23 that exhibited sufficient tumour burden for DNA extraction. The most common age group was 40-49 years. HIV status was as follows: two HIV-positive, 14 HIV-negative and 7 HIV unknown. DNA was extracted from archival FFPE cervical squamous cell carcinoma samples using QIAGEN QIAamp® DNA FFPE Tissue kit. Housekeeping genes were detected by endpoint PCR using standard primers for glyceraldehyde 3-phosphate dehydrogenase (GAPDH) sequences to determine the quality and integrity of extracted DNA for downstream PCR amplification experiments. HrHPV DNA amplification was optimised using a touchdown PCR technique with L1 consensus gene GP5+/GP6+ primers. HrHPV genotypes were detected using a four colour multiplex hrHPV genotyping kit. Samples showing positive results in overlapping probe filter detection spectra were subjected to DNA Sanger sequencing for final confirmation of specific hrHPV genotype. Results: Standard xylene DNA extraction methods using QIAamp® system yielded adequate amounts of DNA with average final concentration of 463.2 ng/l and A260/A280 ratio of 1.86. Housekeeping genes were successfully detected in all samples, confirming that no significant DNA degradation of target sequences occurred within the archival time range of 2004-2014. HPV L1 detection via GP5+/GP6+ primers with endpoint PCR was not achieved via standard cycling conditions and required the use of a touchdown technique with gradually decreasing annealing temperatures. This method successfully identified HPV L1 sequences in 22 out of 23 cases. Multiplex RT-PCR with four colour hydrolysis probes identified hrHPV genotypes in 22 of 23 cases with relative frequencies of HPV genotypes: 16>>18=39=45>33. Most cases showed infection with a single hrHPV genotype (HPV 16 and one case with HPV 33) with four cases demonstrating two genotypes (two with HPV 16&18, one with 16&33 and one with 39&45) and one case with three genotypes (HPV 16, 39, 45). Interestingly, none of the HIV-positive cases showed multiple hrHPV genotype infection. Four hrHPV cases with overlapping spectra for HPV 18/31 and 45/59 were subjected to Sanger sequencing for confirmation of genotype. Three of four cases showed 100% match for genotypes 18 and 45 with the final case demonstrating only co-infective HPV 16.Conclusion: Commercial DNA extraction kits yield adequate amounts of intact, amplifiable DNA in archival FFPE cervical carcinoma specimens. Touchdown PCR is necessary for HPV detection in extracted FFPE DNA cases using GP5+/GP6+ L1 primers. RT-PCR using multicolour hydrolysis probes is a rapid, sensitive technique for hrHPV genotype screening of cervical squamous cell carcinoma specimens. A three colour detection system rather than four colour kit is recommended for future studies in order to avoid extra cost in DNA sequencing cases with overlapping spectra. This pilot study demonstrates hrHPV genotype prevalence similar to that in other populations and suggests that vaccination with currently available formulations would provide a sufficiently wide coverage of HPV genotypes. Future studies will include application of the FFPE DNA extraction, endpoint PCR and RT-PCR techniques to the remainder of the cases in the original cohort.
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Alexander, Rashada Corine. "INSIGHTS INTO ENZYMATIC MANIPULATIONS OF NUCLEIC ACIDS." UKnowledge, 2005. http://uknowledge.uky.edu/gradschool_diss/283.
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This dissertation details three studies dealing with the manipulation of nucleicacids. In the first investigation, each of the four natural nucleobases were analyzed for theability to serve as a universal template at the ligation junction of a T4 DNA ligasereaction. This resulted in the first instance of sequence-independent ligation catalyzed byany DNA ligase. Although all of the nucleobases display universal templatingcapabilities, thymidine and guanosine provided the most effective results. In addition,lowered MgCl2 and ATP concentrations, as well as the inclusion of DMSO, also aided inthe sequence-independent ligation reported here. In the course of these studies, currentmethods of removing urea from denaturing-gel purified nucleic acids provedcumbersome. Therefore, in the second study simple butanol extraction was examined as ameans to eliminate urea from nucleic acid solutions. Stepwise butanol extraction was themost effective approach to solving this problem and provided a much needed techniquefor nucleic acid purification. This type of extraction also does not result in significantlosses of nucleic acid sample. The third study exploits the molecular recognition andcatalytic properties inherent in an autocatalytic group I intron to develop a ribozyme thatcan replace the 5' end of an RNA substrate with a different RNA. This 5' replacementsplicing reaction can potentially repair mutations on the 5' ends of RNA transcripts thatlead to a variety of genetic mutations. The model system was a common mutation in asmall model mimic of the k-ras gene in vitro, which predisposes individuals to lungcancer. This 5' replacement splicing reaction occurred in vitro using this small modelsystem; the reaction was also enhanced by the alteration of the molecular interactionsinvolved. The results and implications of each of these studies are detailed in thisdissertation.
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Borgiel, Björn. "En studie för att kontrollera känsligheten av primers för lake (Lota lota), lax (Salmo salar) och öring (Salmo trutta)." Thesis, Karlstads universitet, Institutionen för miljö- och livsvetenskaper (from 2013), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-67611.
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eDNA is a fast and popular method to collect information about species presence in the environment. eDNA is DNA that is collected from environmental samples, such as water, from DNA that is expelled from organisms interacting with their environment. eDNA is an effective way to find species with small populations and alien species. There are two ways to analyze eDNA, with high-throughput DNA sequencing methods and DNA metabarcoding or use of species-specific primers and PCR. In this study, we focus on the latter, designing species-specific primers for Burbot, Brown trout, and Atlantic Salmon, testing their validity in detecting eDNA of these species with functional PCR. We also evaluated eDNA collection methods, testing different scenarios in aquarium tanks with different number of dead and alive fishes. Primers and experimental setup such as use of different temperatures of the PCR reaction used in this study didn’t result in a functional PCR as determined by electrophoresis gel. There are some problems with the design of the PCR methods for eDNA since the purpose is to design methods that can identify certain species. However, future development of eDNA methods will probably include sequencing and not detection of PCR product sizes. eDNA methods will complete traditional trapping methods like net and electrofishing, but not replace them.eDNA är en snabb och populär metod för att samla information om arters abundans i miljön. eDNA är DNA taget från miljö prover, så som vatten, från DNA som frigörs från organismer som intrigerar med deras miljön. eDNA är ett effektivt sätt att hitta arter med små populationer och främmande arter. De finns två olika sätt att analysera eDNA, med DNA-sekvenseringsmetoder med hög genomströmning och DNA-metabarkodning eller användning av artspecifika primrar och PCR. I denna studie fokuserade vi på den senare, designade artspecifika primers för lake, lax och öring, testa deras validitet vid detektering av eDNA hos dessa arter med funktionell PCR. Vi utvärderade också eDNA-insamlingsmetoder, testa olika scenarier i akvarietankar med olika antal döda och levande fiskar. Primers och experimentell uppställning, såsom användning av olika temperaturer för PCR-reaktionen som användes i denna studie, resulterade inte i en funktionell PCR såsom bestämd av elektroforesgel. Det finns några problem med utformningen av PCR-metoderna för eDNA, eftersom syftet är att utforma metoder som kan identifiera vissa arter. Emellertid kommer framtida utveckling av eDNA-metoder troligtvis att inkludera sekvensering och inte detektering av PCR-produktstorlekar. eDNA-metoder kommer att komplettera traditionella fångstmetoder som nät- och elektrofiske, men inte ersätta dem.
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Florez, Suarez Edson Alejandro. "Détection des effets indésirables des médicaments dans les notes cliniques." Thesis, Université Côte d'Azur, 2020. http://www.theses.fr/2020COAZ4034.
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L'extraction d'information de textes médicaux fournit des renseignements très utiles pour identifier les effets indésirables dans la surveillance après consommation (Pharmacovigilance), qui sont plus difficiles à découvrir à travers des études médicales typiques puisque les patients prennent plusieurs traitements en même temps. Récemment, les techniques de Data Mining ont permis de découvrir les connaissances enregistrées dans de grands ensembles de données, comme les dossiers cliniques collectés par les hôpitaux tout au long de la vie du patient. L'objectif de cette thèse est d'identifier les effets indésirables causés par les traitements. Pour cela, nous devons extraire les relations entre les médicaments et Adverses Drug Events (ADE), qui est la relation de réaction indésirable des médicaments. Ce problème est divisé en tâches de reconnaissance d'entités nommées (NER) et d'extraction de relations. Aujourd'hui, les approches supervisées basées sur des algorithmes de Deep Learning et Machine Learning résolvent ce problème dans l'état de l'art. Les méthodes supervisées ont besoin de caractéristiques riches afin d'apprendre des modèles efficaces au cours de la formation, par conséquent, nous nous concentrons sur la construction de représentations de mots larges (l'entrée du réseau neuronal), nous utilisons des représentations de mots basées sur des caractères et des représentations de niveau de mots. La représentation proposée améliore la performance du modèle de référence et le modèle final a atteint les performances des méthodes de pointe. Ensuite, nous avons extrait des informations contextuelles à travers des modèles de Deep Learning, afin d'identifier les réactions indésirables aux médicaments. Le modèle proposé a amélioré la précision globale et l'extraction des réactions indésirables aux médicaments obtenu avec le modèle de base, ce qui indique l'efficacité de combiner des modèles de Deep Learning et une vaste ingénierie des caractéristiquesThe Information Extraction from clinical notes provides relevant information to identify adverse side effects in post-marketing surveillance of medications (Pharmacovigilance), which is more difficult to discover by traditional medical studies since patients are taking several treatments at the same time. In recent years, data mining techniques have allowed to discover knowledge stored in big datasets, such as the clinical records collected by hospitals throughout patient's life. The goal of this work is identify adverse side effects caused by treatments. Then, we have to identify relations between medications and Adverse Drug Events (ADE) entities, which is called Adverse Drug Reaction relation. This problem is divided Named Entity Recognition (NER) and Relation Extraction tasks. Nowadays, supervised approaches based on Deep Learning and Machine Learning algorithms solve this problem in the state of the art. These supervised systems require rich features in order to learn efficient models during training, therefore, we focus on building comprehensive word representations (the input of the neural network), using character-based word representations and word representations. The proposed representation improves the performance of the baseline model, and the final model reached the performances of state of the art methods. Then we have extracted contextual information through Deep Learning models and other different features obtained from the relations, in order to identify the Adverse Drug Reaction relations. The proposed model improved the overall accuracy and the extraction of Adverse Drug Reaction compared to the baseline, indicating the effectiveness of combining Deep Learning models and extensive feature engineering
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Baral, Sudip. "BREWERS’ SPENT GRAIN CONVERSION TO VALUE-ADDED CHEMICALS BY LAB-SYNTHESIZED HETEROGENEOUS PHOTOCATALYSTS UNDER VISIBLE LIGHT AND MILD CONDITIONS." OpenSIUC, 2021. https://opensiuc.lib.siu.edu/theses/2857.
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Over the last several decades, there have been a tremendous developments and greatinnovations in photocatalysis process along with the development of efficient nanosized catalysts for simple approach and economic viability. In this study, magnetic core@doubleshell nanomaterials were investigated and synthesized in lab with three-step innovative approach where Fe3O4 nanoparticles (NPs) were produced first to act as cores without using any surfactants. The magnetite/silica core–shell structure was then prepared by hydrolysis of tetraethoxysilane (TEOS) in the presence of core particles under alkaline conditions. And the outermost shell, the α-Fe2O3/TiO2 nanoparticles, were grown over magnetic core of Fe3O4@SiO2 using coprecipitation and calcination method. Furthermore, the Fe3O4@SiO2@α-Fe2O3/TiO2 NPs were then loaded on the reduced graphene oxide (r-GO) using hydrothermal method and are also mixed by kneading with the layered double hydroxides (LDH) of Mg2+ and Al3+. These nanoparticles were characterized with scanning electron microscope (SEM), transmission electron microscope (TEM), dynamic light scattering (DLS), and energy dispersive X-ray spectroscopy (EDS). Different model compounds like microcrystalline cellulose (90 μm), D-xylose, and sodium lignosulfonate representing cellulose, hemicellulose, and lignin, respectively, were converted to valuable chemicals with different NPs under visible light for different time periods. For example, valeric acid (VA) and vanillylmandelic acid (VMA) were produced when cellulose was used for the conversion with core-double shell NPS which were quantified using high performance liquid chromatography (HPLC). Similar approach was adopted for the conversion of brewers’ spent grain (BSG), a lignocellulosic biomass, without oxygen under visible light, which yielded ethanol as the main product along with other sugars and acids of very low concentrations. The magnetic property of the nanomaterials made it easy for recycle and reuse. From a sustainability point of view, this study will fill a large need in the biomass photocatalysis field by developing core-shell multi-functional photocatalysts for direct transformation of lignocellulose into valuable chemicals under low temperatures, atmospheric pressure, and visible light from the sun.
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K'Zherho, Régis. "Étude de réactions d'oxydoréduction d'actinides couplées à des phénomènes de transfert liquide-liquide : cas de la désextraction de l'acide nitreux en présence de composé antinitreux en phase aqueuse." Vandoeuvre-les-Nancy, INPL, 1997. http://www.theses.fr/1997INPL025N.
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Cette étude s'inscrit dans le cadre du procédé PUREX de retraitement des combustibles irradiés. Elle a pour objectif l'analyse de l'influence d'une réaction chimique d'oxydoréduction sur la cinétique de transfert liquide-liquide. Le système chimique choisi correspond au cas de la désextraction de l'acide nitreux, d'une phase organique de phosphate de tributyle vers une solution aqueuse d'acide nitrique, en présence d'un composé antinitreux, le nitrate d'hydrazinium. L’analyse bibliographique a permis de mettre en exergue l'importance des phénomènes interfaciaux pour l'extraction liquide-liquide par le phosphate de tributyle. Une technique d'étude, basée sur l'utilisation d'une cellule du type ARMOLLEX, a été alors retenue. L’étude de l'influence des paramètres hydrodynamiques et physico-chimiques a permis de différencier la nature du régime cinétique : diffusionnel puis chimique. En l'absence de composé antinitreux, la résistance au transfert diffusionnel est essentiellement localisée du coté aqueux. La présence du nitrate d'hydrazinium se traduit par une forte accélération de la cinétique de transfert, imputée non seulement à l'annulation de la résistance diffusionnelle aqueuse, mais également à l'intervention directe du nitrate d'hydrazinium sur l'acide nitreux adsorbé à l'interface. Si la cinétique de la réaction d'oxydoréduction, connue par ailleurs pour sa rapidité en phase aqueuse, permettait de prévoir le premier effet, la contribution interfaciale constitue un résultat original qui, à notre connaissance, n'avait jamais été mis en évidence auparavant. Un mécanisme réactionnel prenant en compte cette réaction interfaciale a été élaboré et validé. Pour conforter l'ensemble des résultats établis, d'autres études complémentaires ont été entreprises. Un phénomène surprenant de blocage du transfert a été observé dans le cas d'un autre composé antinitreux, le nitrate d'hydroxylammonium, démontrant toute la spécificité du nitrate d'hydrazinium.
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Funada, Mikaela Renata. "Avaliação de métodos de extração de DNA de Cryptosporidium spp. em amostras fecais e comparação de nested PCR com o médodo coproparasitológico de centrífugo-flutuação em sacarose." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/10/10134/tde-17042009-153638/.
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O desempenho de seis métodos de extração de DNA de oocistos de Cryptosporidium spp. em fezes foram avaliados pela nested PCR do gene SSU rRNA. Os métodos consistem na combinação com pequenas variações de duas técnicas para a liberação de esporozoítos (indução de excistamento/E ou choque térmico/C) e três técnicas de purificação de DNA (fenol-clorofórmio/F, GuSCN-sílica/S ou kit QIAmp DNA Stool Mini/K). Para a avaliação da sensibilidade analítica, os testes foram realizados a partir de diluições seriadas de oocistos purificados, na ausência e na presença de 100 μl de fezes bovinas. A sensibilidade diagnóstica foi avaliada pela comparação com o método microscópico de centrífugo-flutuação em sacarose (padrão-ouro) em 15 amostras fecais de diferentes hospedeiros naturalmente infectados. Na ausência de fezes, foram avaliados apenas os métodos EF, ES, CF e CS, sendo que EF apresentou sensibilidade analítica superior, possibilitando a detecção de até 1 oocisto. Na presença de fezes, os métodos EF, EK e CK apresentaram desempenhos equivalentes, com sensibilidade de 104 oocistos. As maiores sensibilidades diagnósticas foram obtidas pelos métodos EK e CK, que possibilitaram a detecção de 13 (86,7%) das 15 amostras. Devido à alta sensibilidade analítica de EF em amostras purificadas, avaliou-se sua sensibilidade diagnóstica em amostras de oocistos purificados pelo método de centrífugo-flutuacão em sacarose, obtendo-se 100% de detecção. A presença de inibidores nas amostras fecais reduziu fortemente a sensibilidade das reações de PCR a partir de DNA extraído pelos métodos avaliados, sendo recomendável o emprego de técnicas de purificação de oocistos previamente à extração de DNA. Os resultados apontam para uma melhor eficiência dos métodos de indução de excistamento e kit QIAmp DNA Stool Mini.The performance of six methods for DNA extraction from Cryptosporidium spp. oocysts in feces were evaluated by nested PCR of SSU rRNA gene. The methods are the combination with small variations of two techniques for the release of sporozoites (induction of excystation/E or thermal shock/C) and three techniques for DNA purification (phenol-chloroform/F, GuSCN-silica/S or QIAmp DNA Stool Mini kit/K). For the evaluation of analytical sensitivity, tests were made from serial dilutions of purified oocysts, in absence and in presence of 100 μl of cattle feces. The diagnostic sensitivity was assessed by comparison with the microscopic method of centrifugalflotation in sucrose (gold standard) in 15 fecal samples from different naturally infected hosts. In the absence of feces, only methods EF, ES, FC, and CS were tested. EF had the highest analytical sensitivity, enabling the detection of up to 1 oocyst. In the presence of feces, methods EF, EK, and CK showed similar performance, with sensitivity of 104 oocysts. The highest sensitivities were obtained by methods EK and CK, which enabled the detection of 13 (86.7%) of 15 samples. Due to the high analytical sensitivity of EF in purified samples, its diagnostic sensitivity was evaluated in samples of purified oocysts by the method of centrifugal-flotation in sucrose, resulting in 100% detection. The presence of inhibitors in fecal samples greatly reduced the sensitivity of the PCR reactions from DNA extraction methods evaluated, and the use of techniques for purification of oocysts prior to DNA extraction is recommended. The results show a better performance of the methods of induction of excystation and QIAmp DNA Stool Mini kit.
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Qi, Lining. "I. Flow injection capillary electrophoresis using on-line enzymatic and dye interaction reactions II. Mini-solid phase extraction of pharmaceuticals and phospholipids in conjunction with nano-electrospray mass spectrometry." Oxford, Ohio : Miami University, 2003. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=miami1059077676.
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Thesis (Ph. D.)--Miami University, Dept. of Chemistry and Biochemistry, 2003.Title from first page of PDF document. Document formatted into pages; contains xvi, 254 p. : ill. Includes bibliographical references.
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Hayouni, Safa. "Préparation et caractérisation de solvants biosourcés pour des applications synthétiques et environnementales." Thesis, Reims, 2016. http://www.theses.fr/2016REIMS019/document.
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De nouveaux liquides ioniques (LIs) contenant un cation phosphonium ou un cation ammonium couplé à un anion dérivé d’acides biosourcés (L-lactate, L-tartrate, malonate, succinate, L-malate, pyruvate, D-glucuronate, D-galacturonate, férulate, p-coumarate) ont été préparés suivant une réaction acido-basique simple et quantitative. Une nouvelle famille de liquides ioniques dendritiques (LIDs) a également été préparée à partir des dendrimères commerciaux (PPI et PAMAM). Les composés synthétisés ont tous été caractérisés par les méthodes usuelles d’analyses (RMN multinoyaux, SM, AE, IR) mais également par des techniques propres aux liquides ioniques (DSC, ATG, viscosité …).Ces solvants ont montré une efficacité avec la possibilité de recyclage du système catalytique [LI+ « Pd »] dans des réactions d’hydrogénations d’alcènes, de polyènes et de cétones α,β-insaturées dans des conditions douces de température et de pression. Ainsi, l’utilisation de ces LIPhs (liquides ioniques à base de phosphonium) permet d’obtenir d’excellents résultats notamment dans le cas de couplage pallado-catalysé de Heck sur 5 cycles sans perte de la réactivité.Les LIDs quant à eux ont été utilisés pour la récupération de quelques métaux lourds sous forme de cations (Cu2+, Ni2+, Pb2+, Cd2+, Ag+) dans des solutions aqueuses. Quelle que soit la nature du LI utilisé (hydrophile ou hydrophobe), d’excellents taux d’extraction sont obtenus sans modification du pH initialNew biomass derived ionic liquids (ILs) containing phosphonium or ammonium cations with natural organic derived anions (L-lactate, L-tartrate, malonate, succinate, L-malate, pyruvate, D-glucuronate, D-galacturonate, férulate, p-coumarate) were easily prepared with good yields. Other dendritic ionic liquids (DILs) were also obtained from commercial PPI or PAMAM dendrimers. These DILs are containing NTf2 or BF4 anions. The characterization of all ILs was realized through classical NMR, IR, MS and elemental analysis techniques; their viscosity and ATG parameters were also determined.These new solvents proved good performance and recyclability for the selective Pd-catalyzed hydrogenation of alkenes, polyenes and also for the enantioselective hydrogenation of α,β-unsaturated ketones under mild temperature and hydrogen pressure conditions. Furthermore, they showed excellent performances (reaction yields and recycling) for the Heck coupling reaction.Finally, the hydrophilic and hydrophobic DILs were used for removal of metallic ions (Cu2+, Ni2+, Pb2+, Cd2+, Ag+) present in contaminated water and the results of the study proved their excellent catching behaviour
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Kanbe, Yuichi. "Control of Alloy Composition and Evaluation of Macro Inclusions during Alloy Making." Doctoral thesis, KTH, Tillämpad processmetallurgi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-27773.
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In order to obtain a good performance and predict the properties of alloys, it is necessary to control the contents of alloying elements and to evaluate a largest inclusion in the product. Thus, improved techniques for both control of alloy elements and evaluation of the large inclusion in products will enable us to provide better qualities of the final products. In the case of one Ni alloy, (NW2201, >99 mass%Ni), the precise control technique of Mg content is important to obtain a good hot-workability. Hereby, the slag/metal reaction experiments in a laboratory have been carried out at 1873 K, so that the equilibrium Mg content and kinetic behavior can be understood. More addition of Al in the melt as well as higher CaO/Al2O3 value of slag resulted in higher amount of Mg content in Ni. For the same conditions of Al content and slag composition, the mass transfer coefficient of Mg in molten Ni was determined as 0.0175 cm/s. By applying several countermeasures regarding the equilibrium and kinetic process to the plant trials, the value of the standard deviation for the Mg content in an alloy was decreased till 0.003 from 0.007 mass%. The size measurements of largest inclusions in the various alloys (an Fe-10mass%Ni alloy, 17CrMo4 of low-C steel and 304 stainless steel) were carried out by using statistics of extreme values (SEV). In order to improve the prediction accuracy of this method, three dimensional (3D) observations were applied after electrolytic extraction. In addition, the relationship of extreme value distribution (EVD) in the different stages of the production processes was studied. This was done to predict the largest inclusion in the products at an early stage of the process. A comparison of EVDs for single Al2O3 inclusion particles obtained by 2D and 3D observations has clarified that 3D observations result in more accurate EVD because of the absence of pores. Also, it was found that EVD of clusters were larger than that of single particles. In addition, when applying SEV to sulfide inclusions with various morphologies, especially for elongated sulfides, the real maximum sizes of them were able to be measured by 3D observations. Geometrical considerations of these particles clarified the possibility of an appearance of the real maximum inclusion sizes on a cross section to be low. The EVDs of deoxidation products in 304 stainless steel showed good agreement between the molten steel and slab samples of the same heat. Furthermore, the EVD of fractured inclusion lengths in the rolled steel were estimated from the initial sizes of undeformed inclusions which were equivalent with fragmented inclusions. On the other hand, from the viewpoint of inclusion width, EVD obtained from perpendicular cross section of strips was found to be useful to predict the largest inclusion in the final product with less time consumption compared to a slab sample. In summary, it can be concluded that the improvement of the techniques by this study has enabled to precisely control of alloy compositions as well as to evaluate the largest inclusion size in them more accurately and at an earlier stage of the production process.QC 20101222
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Khalfalla, Hamza Abdulmagid. "Modelling and optimisation of oxidative desulphurization process for model sulphur compounds and heavy gas oil : determination of rate of reaction and partition coefficient via pilot plant experiment : modelling of oxidation and solvent extraction processes : heat integration of oxidation process : economic evaluation of the total process." Thesis, University of Bradford, 2009. http://hdl.handle.net/10454/4247.
Full textAbstract:
Heightened concerns for cleaner air and increasingly more stringent regulations on sulphur content in transportation fuels will make desulphurization more and more important. The sulphur problem is becoming more serious in general, particularly for diesel fuels as the regulated sulphur content is getting an order of magnitude lower, while the sulphur contents of crude oils are becoming higher. This thesis aimed to develop a desulphurisation process (based on oxidation followed by extraction) with high efficiency, selectivity and minimum energy consumption leading to minimum environmental impact via laboratory batch experiments, mathematical modelling and optimisation. Deep desulphurization of model sulphur compounds (di-n-butyl sulphide, dimethyl sulfoxide and dibenzothiophene) and heavy gas oils (HGO) derived from Libyan crude oil were conducted. A series of batch experiments were carried out using a small reactor operating at various temperatures (40-100 °C) with hydrogen peroxide (H2O2) as oxidant and formic acid (HCOOH) as catalyst. Kinetic models for the oxidation process are then developed based on 'total sulphur approach'. Extraction of unoxidised and oxidised gas oils was also investigated using methanol, dimethylformamide (DMF) and N-methyl pyrolidone (NMP) as solvents. For each solvent, the 'measures' such as: the partition coefficient (KP), effectiveness factor (Kf) and extractor factor (Ef) are used to select the best/effective solvent and to find the effective heavy gas oil/solvent ratios. A CSTR model is then developed for the process for evaluating viability of the large scale operation. It is noted that while the energy consumption and recovery issues could be ignored for batch experiments these could not be ignored for large scale operation. Large amount of heating is necessary even to carry out the reaction at 30-40 °C, the recovery of which is very important for maximising the profitability of operation and also to minimise environmental impact by reducing net CO2 release. Here the heat integration of the oxidation process is considered to recover most of the external energy input. However, this leads to putting a number of heat exchangers in the oxidation process requiring capital investment. Optimisation problem is formulated using gPROMS modelling tool to optimise some of the design and operating parameters (such as reaction temperature, residence time and splitter ratio) of integrated process while minimising an objective function which is a coupled function of capital and operating costs involving design and operating parameters. Two cases are studied: where (i) HGO and catalyst are fed as one feed stream and (ii) HGO and catalyst are treated as two feed streams. A liquid-liquid extraction model is then developed for the extraction of sulphur compounds from the oxidised heavy gas oil. With the experimentally determined KP multi stage liquid-liquid extraction process is modelled using gPROMS software and the process is simulated for three different solvents at different oil/solvent ratios to select the best solvent, and to obtain the best heavy gas oil to solvent ratio and number of extraction stages to reduce the sulphur content to less than 10 ppm. Finally, an integrated oxidation and extraction steps of ODS process is developed based on the batch experiments and modelling. The recovery of oxidant, catalyst and solvent are considered and preliminary economic analysis for the integrated ODS process is presented.
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LAKKIS, ZAHREDDINE ZEINAB. "Aspects thermodynamiques et cinetiques de l'extraction de metaux divalents par des acyl-4-pyrazolones-5." Strasbourg 1, 1986. http://www.theses.fr/1986STR13001.
Full textAbstract:
Extraction de cd et zn a partir des milieux aqueux, perchlorate, nitrate et sulfate par des melanges de phenyl-1 methyl-3 benzoyl-4 pyrazolone-5 et de sels d'ammonium lipophiles. Le pyrazolonate de nh::(4) est l'agent reel de synergie. Mecanisme de transport de cuivre par des acyl-4 pyrazolones-5 a travers une membrane liquide epaisse
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McCarney, Jonathan Paul. "Reactions and process separations in environmentally benign media." Diss., Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/30362.
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Ribeiro, Daniella Carvalho. "Comparação de protocolos de extração de DNA para detecção de Mycobacterium bovis através da PCR em homogeneizados de órgãos bovinos." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/10/10134/tde-07032007-115429/.
Full textAbstract:
A tuberculose bovina, cujo agente etiológico é o Mycobacterium bovis, é uma zoonose de caráter crônico que representa uma das principais enfermidades em rebanhos bovinos. Devido às perdas consideráveis de bacilos viáveis nos processos de descontaminação, e também pelo consumo de várias semanas entre o isolamento primário e a identificação final da espécie, métodos moleculares funcionam como metodologia diagnóstica auxiliar à bacteriologia clássica. Estes métodos têm ampla aplicação no diagnóstico e tipificação da tuberculose bovina, no entanto, a baixa sensibilidade quando aplicados diretamente sobre homogeneizados de tecidos tem limitado sua difusão como método diagnóstico de rotina. A solução do problema, ao que tudo indica, passa por métodos de extração mais eficientes e menos vulneráveis aos fatores inibidores da amplificação. Assim, foram selecionadas 60 lesões granulomatosas de 60 bovinos condenados em abatedouro, 30 positivas ao isolamento de Mycobacterium bovis (padrão ouro positivo) e 30 negativas (padrão ouro negativo). Dessas lesões foram obtidos homogeneizados que foram submetidos a diferentes protocolos de extração de DNA, que por sua vez foram todos submetidos ao mesmo protocolo de amplificação. Os resultados mostraram que o protocolo de BOOM et al. (1990) modificado apresentou sensibilidade superior ao isolamento de M. bovis pelo método clássico.The bovine tuberculosis, whose etiological agent is the Mycobacterium bovis, is a major zoonosis of cattle, of chronical course. Due to the expressive loss of viable bacilli during the decontamination processes and the long period between the primary isolation and the final identification of the specie, molecular methods are being used as auxiliary diagnostic methods to the classical bacteriology. These methods have a broad scope of application in the diagnosis and typification of bovine tuberculosis. However, the low sensibility when applied directly to tissue homogenates have limited its application as routine diagnostic method. The answer to this problem, as it seems, is the development of extraction methods that are more efficient and less vulnerable to inhibition factors of amplification. Therefore, 60 granulomatous lesions of 60 condemned bovines at abattoir were selected, 30 Mycobacterium bovis isolation positives (positive gold standard), and 30 negatives (negative gold standard). The homogenates were obtained from these lesions and were subjected to different DNA extraction protocols, all of which were submitted to the same amplification protocol. The results showed that BOOM et al. (1990) modified protocol showed superior sensibility than the M. bovis isolation through the classical method.
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Lukhezo, Muchinyarawo. "Reactive solvent extraction of amino acids." Thesis, London South Bank University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.245090.
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Raveu, Gaëlle. "Optimisation de la fabrication par carbothermie de carbure d'uranium à teneur en oxygène maitrisée." Thesis, Orléans, 2014. http://www.theses.fr/2014ORLE2071/document.
Full textAbstract:
Pour les réacteurs de génération IV, les carbures mixtes (U,Pu)C, avec leur grande densité en atomes fissiles et leurs excellentes propriétés thermiques, sont potentiellement des combustibles à la fois économiques (coeurs plus compacts et plus efficaces) et sûrs (marge à la fusion élevée). Un bon simulant de l’(U,Pu)C pour des études R&D sur son comportement est l’UC, puisqu’ils possèdent des structures très similaires. La synthèse par carbothermie a été utilisée car elle est la plus étudiée et celle actuellement envisagée industriellement. Cependant, elle implique la manipulation de poudres : sous air, le carbure peut réagir très violemment à température ambiante, et sous atmosphère contrôlée il est susceptible d’absorber les impuretés. Une installation inertée sous Ar, BàGCARA, a donc été utilisée. Les améliorations du procédé de fabrication ont notamment portés sur l’atmosphère de frittage afin d’évaluer l’impact sur la pureté des échantillons (vis-à-vis des quantités d’oxygène). La méthode originale d’analyse par faisceau d’ions a permis de déterminer la composition de surface (profils d’oxygène en profondeur dans les premiers 1 μm et stoechiométrie moyenne). Elle a pour la première fois été mise en oeuvre pour l’analyse de l’oxygène dans les matériaux carbonés. Les analyses DRX ont montré le passage par un intermédiaire réactionnel lors de la carbothermie et une meilleure cristallisation des échantillons fabriqués dans BàGCARA. Ils possèdent aussi une meilleure microstructure, densité et aspect visuel que ceux fabriqués par le procédé de référence. Un frittage sous vide mène à un UC plus dense avec moins de secondes phases que les frittages sous Ar, Ar/H2 ou sous contrôle de PC. Cependant, il n’a pas été possible d’analyser les carbures sans passage sous air ce qui peut impacter leur paramètre de maille et mener à leur détérioration. Lorsque l’UC est initialement exempt d’oxygène, il s’oxyde plus vite et plus intensément, de manière hétérogène. Les contraintes mécaniques induites entre les grains mènent à la fracturation du matériau et à une corrosion fissurante, puis à la décohésion du matériau. Une étude des mécanismes d’oxydation serait intéressante afin de valider et de comprendre l’évolution du matériau lorsqu’il est en contact avec l’oxygène. Une étude des mécanismes mis en jeu pourrait être envisagée par couplage des techniques d’EBSD et d’analyse par faisceau d’ions afin de vérifier s’il existe un lien entre une oxydation préférentielle des grains et leur orientation cristallographiqueMixed carbides (U, Pu)C, are good fuel candidate for IVth generation reactors because of their high fissile atoms density and excellent thermal properties for economical (more compact and efficient cores) and safety reasons (high melting margin). UC can be imagine as a surrogate material ror R&D studies on (U,Pu)C fuel behavior, because of their similar structures. The carbothermic reaction was used because it is the most studied and now consider for industrial process. However, it involves powders manipulation : in air, carbide can strongly react at room temperature and under controlled atmosphere it can absorb impurities. An inerted installation under Ar, BàGCARA, was therefore used. Process improvements were carried out, including the sintering atmosphere in order to evaluate the impact on the sample purity (about oxygen content). The original method by ion bearn analysis was used to determine the surface composition (oxygen in-depth profiles in the first microns and stoichiometry). This oxygen analysis was set for the first time in carbonaceous materials. XRD analysis showed the formation of an intermediate compound during the carbothermic reaction and a better crystallization of the samples fabricated in BàGCARA. They also have a better microstructure, density, and visual appearance if compared to former samples. Vacuum sintering leads to a denser UC with fewer second phases if compared to Ar, Ar/H2 or controlled PC atmospheres. However, it was not possible to analyze carbides without air contact which may impact their lattice parameter and lead to their deterioration. When the carbide is initially free of oxygen, it oxidizes faster, more intensely and heterogeneously. The mechanical stress induced between the grains lead to fracturing the material, to corrosion cracking and then a debonding of the material. A study of oxidation mechanisms would be interesting to validate and understand the evolution of the material in contact with oxygen. A study of the mechanisms involved could be considered by coupling EBSD technique and ion beam analysis to check whether there is a link between a preferential oxidation of the grains and their crystallographic orientation
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Zakaria, Rabitah. "Reactive Extraction of Rapeseed for Biodlesel Production"." Thesis, University of Newcastle upon Tyne, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.525042.
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Salam, Kamoru Adio. "Reactive extraction of microalgae for biodiesel production." Thesis, University of Newcastle upon Tyne, 2015. http://hdl.handle.net/10443/3088.
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Fatty acid methyl ester (FAME “biodiesel”) is a renewable transport fuel that can be produced from waste/refined oil, pre-extracted oil from oilseeds or microalgae. The most common method converts extracted oil from biomass to FAME through transesterification using acidified or alkalised methanol. Alternatively, FAME can be made by contacting the oil-bearing biomass directly with an alcohol containing a catalyst. This approach is potentially a cost-effective alternative way of making algal FAME due to its elimination of the solvent extraction step and its higher water tolerance. This study reports reactive extraction of Nannochloropsis occulata and Chlorella vulgaris for FAME production using NaOH, H2SO4, zirconium dodecyl sulphate (“ZDS”) or H2SO4/SDS (a surfactant) as catalysts. It is possible to produce FAME using all of them. A relationship was found between FAME yield, catalyst concentration, methanol to oil molar ratio, moisture content or algal cell wall chemistry. NaOH is the most effective catalyst, producing high FAME yields (96 %) in relatively short reaction times (10 min), at 925:1 methanol to oil molar ratio and 0.5N NaOH. This was achieved despite high levels of free fatty acid (6 % lipid) in Chlorella vulgaris. A numerical model derived by Eze et al. (2014) fitted with experimental data from this study shows that other side reactions including FAME and triglyceride saponification, free fatty acid neutralisation occur alongside the desired FAME synthesis in a NaOH-catalysed reactive extraction. Regardless of the catalysts used, methanol to oil molar ratios in the range 600:1-1277:1 caused 5-30 wt %/(wt dry algae) moisture tolerance: significantly greater than the 0.5 wt % oil moisture required in conventional transesterifications. Both the phosphorus mass balance and conversion of the isolated algal phospholipids into FAME revealed that pre-soaking pre-treatment solubilises the phospholipid bilayer to some degree, and iii [Abstract continued] contributes to an increased FAME yield in Nannochloropsis occulata (98.4 %) and Chlorella vulgaris (93.4 %). Residual protein loss in Chlorella vulgaris and Nannochloropsis occulata were respectively 6.5 and 10 %. The carbohydrate content was significantly reduced by 71 % in Chlorella vulgaris and 65 % in Nannochloropsis occulata.
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Pfeuffer, Bernhard [Verfasser]. "Process intensification by heterogeneous reactive extraction / Bernhard Pfeuffer." Clausthal-Zellerfeld : Universitätsbibliothek Clausthal, 2012. http://d-nb.info/1021739839/34.
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Ingr, Adam. "Parní turbína pro biomasovou elektrárnu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2019. http://www.nusl.cz/ntk/nusl-400482.
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This master‘s thesis deals with thermodynamic calculation of condensing steam turbine with controlled extraction point for heat exchanger, into biomass power plant block. Rated output of steam turbine is 6.5 MW and rated output of heat exchanger is 4.5 MW. At the beginning of the thesis is explained the heat scheme and the effect of heat regeneration on the design of turbine. Attention was also paid to the heat equation of individual thermal diagram devices and the calculation of the steam mass flow rate. The next part is focused on thermodynamic calculation of the turbine, followed by mechanical stress calculations. The calculation is divided into preliminary design and detailed calculation. At the end, the performance analysis of the designed turbine is made.
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Rambocus, Subhas. "Reactive solvent extraction of dicarboxylic and carboxylic-sulfonic acids." Thesis, London South Bank University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.245144.
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Ben, Nasr Chérif. "Complexation du nickel (II) et des lanthanides (III) par des phosphoramides bidentes : Application à l'extraction liquide-liquide." Nancy 1, 1986. http://www.theses.fr/1986NAN10032.
Full textAbstract:
Les composés de type (NME::(2))::(2)P(O)NRP(O)(NME::(2))::(2) complexent fortement lésions métalliques et peuvent être utilisés en tant qu'agents extractaires dans l'extraction liquide liquide. Synthèse systématique des complexes lanthanides-NDA. L'étude RMN a permis également de trier les contributions de contact et de pseudo-contact au déplacement paramagnétique des protons et des phosphores du ligand engagé dans le complexe et d'obtenir des informations concernant la structure des complexes en solution. Enfin, le problème de l'extraction liquide-liquide des lanthanides par le NIPA dans le nitrométhane a été abordé. Les résultats obtenus ont révélé que le NIPA est un excellent agent extractant, notamment en milieu nitrique, et que l'efficacité de l'extraction augmente quand le rayon atomique diminue
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Barakat, Salem Ahmad Salem. "Spectroscopic and flow-injection studies of some novel ion-pair reactions." Thesis, Queen's University Belfast, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317545.
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Xu, Xin. "Direct conversion of carboxylate salts to carboxylic acids via reactive extraction." Texas A&M University, 2008. http://hdl.handle.net/1969.1/86006.
Full textAbstract:
The MixAlco process, a proprietary technology owned by Texas A&M
University, converts biomass (e.g., municipal solid waste, sewage sludge, paper,
agricultural residues, and energy crops) into usable chemicals (e.g., acetic acid) and fuels
(e.g., ethanol). Historically, calcium carbonate has been used as the buffer. Recently, it
was found that using ammonium bicarbonate as the buffering agent enhances the
fermentation conversion. In this case, fermentation broth contains ammonium salts (e.g.,
ammonium acetate, propionate, butyrate, pentanoate). Therefore, the downstream
processing steps (including extraction, purification, esterification, and product
separation) must be compatible with the ammonium carboxylate salts formed in the
fermentation.
This research focuses on converting fermentation broth carboxylate salts into
their corresponding acids via "acid springing." Reactive extraction and thermal
conversion (distillation) are crucial parts of the acid springing process. Because the components of the fermentation broth are over 80% ammonium
acetate and 20% other ammonium carboxylate salts (ammonium propionate, butyrate,
pentanoate, etc.), all the initial experiments in this study were performed using reagentgrade
ammonium acetate to simplify the reaction. Later, actual fermentation broth was
employed.
The primary objective of this study was to provide the optimal operating
conditions to make the downstream processing steps of the MixAlco process compatible
with ammonium carboxylate salts formed in the fermentation. The optimal initial
concentration for reactive extraction should be 150-200 g/L and the volume ratio of
aqueous phase and extractant should be 1:1. The distribution coefficient reaches the
maximum value when the concentration of TOA is 20% (vol %) in n-octanol. The batch
distillation study shows that there are two reaction stages: (1) water leaves the system at
100-106 °C and (2) the acid-amine complex decomposes at 160-180 °C.
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ELACHAWI, SAKHER. "Les reactions parodontales dans le site d'extraction au cours du deplacement orthodontique." Paris 7, 1991. http://www.theses.fr/1991PA07GS01.
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Willersinn, Stefan [Verfasser]. "Reactive Extraction Kinetics in a Membrane-based Microcontactor / Stefan Willersinn." Aachen : Shaker, 2017. http://d-nb.info/1149278234/34.
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McGillivary, Angela. "Reactive solvent extraction of #beta#-lactam antibiotics and other anions." Thesis, London South Bank University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326763.
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Konečná, Jana. "PROBIOTICKÉ GENY POTRAVINÁŘSKY VÝZNAMNÝCH BAKTERIÍ MLÉČNÉHO KVAŠENÍ." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2019. http://www.nusl.cz/ntk/nusl-402108.
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Isolation of deoxyribonucleic acid (DNA) is an important step in the molecular diagnostics of microorganisms. A high quality of isolated DNA is necessary for DNA amplification by the polymerase chain reaction (PCR). The conventional DNA isolation using phenol chloroform extraction and DNA precipitation in ethanol is time consuming and requires the use of toxic phenol. Magnetic separation techniques using magnetic solid particles are one of modern methods to speed up the nucleic acids isolation. The aim of this work was to use two different types of magnetic particles for solidphase DNA extraction. The amounts of DNA in separation mixtures were measured using ultraviolet spectrophotometry (UV). The first experimental conditions were tested on chicken erythrocytes DNA. Phosphate buffer (pH 7, 7.6 and 8) was used for adsorption of DNA on magnetic particles. It was shown that approximately almost one half of DNA was adsorbed to the particles. The elution conditions of DNA were also optimized. Secondly, bacterial DNA was tested. This DNA eluted from the particles was in PCR ready quality. High resolution melting (HRM) curve analysis is a simple, low-cost method for amplicon discrimination and easy connection with real-time polymerase chain reaction (PCR). In this contribution, we report rapid species identification of strains belonging to the Lactobacillus group using HRM-PCR. Three different DNA isolation methods were used in this work: phenol extraction, separation using magnetic particles and commercial kit. Ten sets of targeted gene fragments primers (LAC1 – LAC2, LAC2 – LAC4, P1V1 – P2V1, Gro F – Gro R, 3BA-338f – Primer 1, V1F – V1R, CHAU - V3F – CHAU - V3R, CHAU - V6F – CHAU - V6R, poxcDNAFw – poxPromRVC, poxcDNAFw – poxPromRVT) were tested for amplification of the 16S rRNA gene. Use of GroF/R and LAC2/4 primers pairs successfully identify strains belong to the Lactobacillus group. The variance between used extraction methods for evidence of HRM curves was found.
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Konečná, Jana. "Využití molekulárně biologických technik pro identifikaci a analýzu probiotických bakterií." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2019. http://www.nusl.cz/ntk/nusl-402114.
Full textAbstract:
Isolation of deoxyribonucleic acid (DNA) is an important step in the molecular diagnostics of microorganisms. A high quality of isolated DNA is necessary for DNA amplification by the polymerase chain reaction (PCR). The conventional DNA isolation using phenol-chloroform extraction and DNA precipitation in ethanol is time-consuming and requires the use of toxic phenol. Alternative method of DNA isolation is use of commercially available kits which, however, are expensive and their efficiency is low. Magnetic separation techniques using magnetic solid particles are one of modern methods to speed up the nucleic acids isolation. The aim of this work was to use two different types of magnetic particles for solid-phase DNA extraction. Magnetic microparticles P(HEMA – co – GMA) containing –NH2 group and nanoparticles PLL, whitch contains polylysine. The amounts of DNA in separation mixtures were measured using ultraviolet spectrophotometry (UV). The first experimental conditions were tested on chicken erythrocytes DNA. Phosphate buffer (pH 7, 7.6 and 8) was used for adsorption of DNA on magnetic particles. It was shown that approximately almost one half of DNA was adsorbed on the particles. The elution conditions of DNA were also optimized. Secondly, bacterial DNA was tested. After optimalization, the developed method was used for DNA isolation from real food supplements. This DNA eluted from the particles was in PCR ready quality. High resolution melting (HRM) curve analysis is a simple, low-cost method for amplicon discrimination and easy connection with real-time polymerase chain reaction (PCR). In this thesis, we report rapid species identification of strains belonging to the Lactobacillus group using HRM-PCR. Three different DNA isolation methods were used in this work: phenol extraction, separation using magnetic particles and commercial kit. Ten sets of targeted gene fragments primers (LAC1 – LAC2, LAC2 – LAC4, P1V1 – P2V1, Gro F – Gro R, 3BA-338f – Primer 1, V1F – V1R, CHAU - V3F – CHAU - V3R, CHAU - V6F – CHAU - V6R, poxcDNAFw – poxPromRVC, poxcDNAFw – poxPromRVT) were tested for amplification of the 16S rRNA gene. Use of GroF/R and LAC2/4 primers pairs successfully identify strains belong to the Lactobacillus group. The variance between used extraction methods for evidence of HRM curves was found.
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Marbaugh, Kelly Renee. "Theoretical and Experimental Studies on Simultaneous-Isomerization and Reactive-Extraction Followed By Back-Extraction of Biomass Hydrolysate sugars." University of Toledo / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1449876597.
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Smith, Robert James. "Oxidative extraction of chlorinated pulp in a packed bed reactor." Thesis, Georgia Institute of Technology, 1988. http://hdl.handle.net/1853/10265.
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Larson, Christopher L. (Christopher Lee) 1978. "Polonium extraction techniques for a lead-bismuth cooled fast reactor." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/33825.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Nuclear Engineering, 2002.Includes bibliographical references (p. 92-94).
The construction of a next generation fast nuclear reactor using liquid lead-bismuth as a coolant demands the design of applied technology to remove 210Po from the neutron activated lead-bismuth eutectic. Experiments were performed to determine the kinetics of polonium hydride and lead-polonide released from molten lead-bismuth to determine the rate response of gaseous polonium chemical species in contact with various argon and hydrogen gas streams. It was determined that the rate release of polonium hydride is slightly higher at lower temperatures. The kinetic response is also faster with increased hydrogen content, as evident by the determined equilibrium constant. In addition, experiments involving the adsorption of gaseous polonium species on metallic praseodymium were undertaken. Formation of an oxidation layer and physical deterioration of the praseodymium inhibited proper sample analysis. The extraction techniques of rare-earth filtering and polonium hydride stripping and their relative figures of merit were discussed. Of the two techniques, a small-scale design adopting polonium hydride stripping was explored to address basic issues of design, fabrication, operation, and maintenance of an online polonium extraction system. Pending results of further investigation on alkaline extraction and electro-deposition experiments a small-scale design may be pursued.
by Christopher L. Larson.
S.M.
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Gonenc, Zubeyde Sermin. "Coal pyrolysis in a fixed bed reactor." Thesis, Imperial College London, 1989. http://hdl.handle.net/10044/1/47449.
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